Mobile service went down more often than any other kind of broadband service during 2017’s northern California firestorm, but cable, telco and fixed wireless systems also took a severe beating. Satellite Internet service had the highest survivability rate. That’s one conclusion drawn from a wide survey of people in and around Mendocino, Napa and Sonoma counties during an horrific wildfire in October 2017.

Mobile broadband carriers had an 88% failure rate – i.e. people “lost some to all service”. Broadband service from Comcast was down for 73% of customers, while 69% of AT&T and Frontier broadband subscribers experienced outages.

One caveat: the survey did not break AT&T subscribers out by type of service. Comparing total numbers, and also the voice telephone service data collected, it’s a fair conclusion that most of the 700 people who ticked the AT&T Internet service box are landline customers. So that’s how I categorised them, but I’m sure that some mobile customers are mixed in.

DSL resellers – companies that lease copper lines from AT&T or Frontier, add some equipment and provide semi-independent Internet access – only had a 43% failure rate. But that doesn’t mean they did better than the big guys – resellers concentrate their service in cities and towns, and most of the fire damage was in exurban and rural areas. If rural residents can’t buy the service, then they can’t lose it either.

One common problem that all the terrestrial companies in the counties have is that AT&T is pretty much the only middle mile game in town, according to the report. So if an AT&T inter-city line is damaged, all the ISPs using it suffer.

Satellite Internet service, which had a 26% failure rate, isn’t affected by AT&T’s backhaul outages. But it does share one weak link with all the others: electricity. If your power (or your provider’s) goes out and there’s no back up, you don’t have Internet service either. Smoke shouldn’t have been a problem for satellite or other wireless services – any smoke that’s thick enough to block signals is too thick to breath. No one should have been sitting at home trying to get on the Internet at that point.

The data was collected by the North Bay/North Coast Broadband Consortium. More than 3,700 people filled out an online survey. It wasn’t a scientifically selected sample, but just taken for what it is, it’s a significant number of responses.